Carnot's Principle

By the practice of using reversible processes, Sadi Carnot in the year1824 advanced the reading of the second law by revealing a principle consisting of the propositions shown below.

1. No engine can be much proficient than a reversible engine operating among the equivalent high temperature and low temperature reservoirs. Here the word heat reservoir is in use to mean either a heat sink or a heat source.

2. The efficiencies of all reversible engines operating among the similar constant temperature reservoirs are similar.

3. The effectiveness of a reversible engine based only upon the temperatures of the heat receiver and heat source.